<!doctype html>
<html>
  <head>
    <meta charset="UTF-8">
    <title>unused plugin title (your plugin folders name is the title visible to the user)</title>
    <style>
      html, body, #display {
        height: 100%;
      }
      body {
        margin: 0;
      }
      #display {
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 100px;
        color: grey;
      }
      .toolbar {
        position: fixed;
        top: 4%;
        left: 4%;
        width: 50px;
        height: 50px;
        background: pink;
      }
    </style>
  </head>
  <body>
    <div id="display">
      yeah
    </div>
    <script>
      function stop() {
        alert("stopped");
      }

      function init (message) {
        var returned_Value = message.pluginParent.callback(message.pluginParent.callback.TYPE_EXCLUSIVE, stop);
        returned_Value.run();
        var toolbar = returned_Value.toolbarAPI.createToolbar(document.body);
        returned_Value.toolbarAPI.createCheckbox({
          text: "yeha",
          handlerNames: "click",
          click: function() {
            alert(this.value);
          }
        }, toolbar);
      }
    </script>
  </body>
</html>